overheating yellow battery icon lit

First of all, why was the sensor originally replaced? What was the symptom? There are usually two of them, one for the warning light or gauge on the dash and one for the Engine Computer which turns on the electric radiator fan if you have one. Removing either one will let coolant run out of the engine and air to get in so it is normal to have to add coolant after the repair is completed. That air could get trapped and need to be bled out manually. The mechanic should have checked for that by warming up the engine before giving the car back to you. Sometimes they hope the air bleeds out by itself because then they can "punch off" the job sooner at the time clock which saves you money. That air pocket can prevent the thermostat from opening when the engine warms up. Thermostats open in response to hot liquid coolant, not hot air. When the thermostat doesn't open, the coolant can't circulate to the radiator. Sometimes when the engine cools down, that air bubble will shrink and it may work itself out the next time the engine is started. I would suggest driving it again to see if it overheats but make that test drive in the direction of the same repair shop. If it starts steaming on the way there, stop the engine and look to see exactly where the steam is coming from. There could be a leak in a rubber hose, a loose hose clamp, or it could just be hot coolant boiling out of the reservoir. If you have an electric radiator fan, it might not be turning on when the engine temperature calls for it. The clue there is the engine will not overheat at highway speed. Because of the higher speed, there is plenty of air flow through the radiator so the electric fan isn't needed. If the problem continues, go back to the same shop and insist this problem just started with the recent service, keeping in mind I don't know the reason that recent service was needed. If you go to a different shop, it's like going to a new doctor because the first one didn't come up with a diagnosis after the first round of tests. The new mechanic will have to start testing all over and if it is determined the first mechanic caused a problem you will have to pay the second one to resolve it. Reputable shops will take care of their mistakes and oversights, however, if they didn't actually cause the problem you can be expected to have to pay at least for any new parts that are needed. Many shops will donate the labor if the job isn't too involved. I should comment too that I've been witness to many customers thinking they were taken advantage of because they are a woman. The same can be said of men in a suit and tie. Very often I've seen my service adviser shake his head in frustration because he tried to explain something and he knew the customer left feeling ripped off when in fact they tried to help that person. Most service writers walk a fine line between keeping the shop owner happy with profits so they can pay the numerous bills, keeping the mechanic happy with profitable jobs so he can afford to keep buying needed new tools, and keeping the customer happy so they will come back in the future. Many customers don't understand how their cars work so any explanation from the service writer is looked at with suspicion. Also keep in mind that most service writers are good at working with customers; they are not mechanics. They have to read what the mechanic wrote on the repair order or they have to listen to them talk about things about your car that they don't understand themselves, then translate what they don't understand real well into something you WILL understand. It's pretty easy to see how things can get mixed up in translation. You typically don't get that middle man at the doctor's office. Service writers hate having to defend their mechanics actions to a customer, but that's what they have to do very often. As a former instructor at a community college, I often got involved in explaining in understandable terms what was done to a person's car and why. Most of the time that alleviated the owner's anger once they understood why something was done. The problem was that could take an hour or more. You don't want to stand in line waiting for an hour to get your car serviced because the person behind the counter is explaining the repair to the person ahead of you. They have to give the best explanation possible in the shortest amount of time. That means condensing it to the important points and forgetting about the details. Keep in mind that even though you are a woman, 98 percent of mechanics want to fix your car the best they can. It's the other 2 percent that give the entire industry a bad reputation. I worked for the most honest and reputable tv repair shop owner for over 30 years, but that industry also has a bad reputation. You'll find 2 percent of carpenters, plumbers, cable installers, painters, and sales clerks are dishonest but the entire professions are held accountable for the actions of a few because we don't understand why they have to do what they do.